But I don’t want to cut for spoilers. What do you mean, you still haven’t seen the episode? Fine.

Everyone else, I’ll see you below the cut.

Okay. so in Dead Clade Walking, the murder is committed alongside the destruction of a fossil that, on its own, disproved a theory so important, so world changing to the murderer in question that it would ruin his career if it was found out. That fossil was a non-avian dinosaur younger than sixty-five million years old. That… really isn’t enough to get anyone to kill anyone, I’m afraid. There is no important, career building theory that required full extinction at the K-Pg extinction event. It’s pretty uncontroversial that a) non-avian dinosaurs are extinct NOW, b) there was a massive decrease in diversity at the K-Pg Boundary.

It’s also a common consensus that c) dinosaurs did not become extinct at the K-Pg event, because birds, d) there seems to be a decrease in diversity below the K-Pg Boundary anyway – the meteoric impact and possibly other factors just hastened a decline already in progress. It doesn’t matter when dinosaurs went extinct, because we know they did. Oh, and e) the extinction event wiped out 75% of all species, not just dinosaurs. One tyrannosaurid a little bit later would mean nothing.

So, what sort of single fossil could make a palaeontologist kill? Well, for a start, it would have to be so bizarre, so out there, so ridiculous that it would cause someone to throw something across the room in a fit of “what am I even looking at?” rage. Added to that, it had to be something of interest to the sort of palaeontologist likely to take their palaeontology really really seriously. Now, I don’t like to generalise, but the mammal workers I’ve known have generally been pretty easy-going people. The invertebrate palaeontologists love their work, but not enough to kill for it.

Nope, I’ve got to admit, if you want the real, passionate, would-kill-for-it workers in palaeontology, you want us dinosaurologists. But not just any dinosaurologist. Ornithischian workers might have disagreements on the forelimb use of a hadrosaur, but I don’t think we’re likely to kill each other.

4. Gastric Flora in a Tyrannosaurid

I ended up falling on the Great Tyrannosaur Diet Debate. Never has there been a ‘controversy’ as boring and pointless, and so impassioned as Were Tyrannosaurs Predators Or Scavengers. There is real passion on both sides of a discussion that, to me, seems to have very little actual consequence. Killing to eat or eating what they find, the ecological role of the animal is the same, the diet is the same. the only real difference it makes is coolness factor. And only in this particular debate have I heard actual, professional scientists and serious investigators into mesozoic reality, argue for predation on the basis of Rule of Cool.

[Obviously, not all theropod workers are affected by “Our Dinosaurs Are Cooler Than Yours,” and other palaeontologists are definitely not immune to it, but I had to pick one!]

It’s hard to imagine what Absolute Fossil Proof of scavenging or predation would be, but if I wanted to piss off my fictional murderous theropod worker enough to make him a Holmes villain, I could do one better than scavenger – imagine the fury that would come from Super-Cool-Apex-Predator being associated with fossil evidence for omnivory or even herbivory!

We know what T. rex teeth look like, so it’d be hard to argue for a change in diet based on that. But more direct evidence for dieat can come from the actual remains of the diet – sometimes preserved in stomach contents. It’s not unknown for carnivores to be found fossilised with the bones of their last meal in their stomach. Plant-based stomach contents are rarer, partly because plant matter is not as prone to lithification (fossilisation by turning to stone) as bones are. It’s also sometimes hard to tell what are genuine stomach contents and what’s just been washed in by other factors. But just occasionally indisputable plant matter has been found in dinosaur stomachs.

There’s also the existence of gastroliths – pebbles within the stomachs of dinosaurs and extanct archosaurs (birds and crocodiles) that assist in the mechanical breaking down of tough plant matter, and definitely not a carnivore character.

So imagine you’re a theropod-working palaeontologist who is REALLY INVESTED in the idea of Tyrannosaurus rex as a fearsome, pro-active apex predator, and someone shows you a fossil of you favourite bad boy dinosaur with a gastric cavity full of broken up, early flowering plants.